• Title/Summary/Keyword: 자기공명의료영상

Search Result 92, Processing Time 0.029 seconds

Analysis of Learning Effects MRI Education Content based on Virtual Reality (가상현실 기반 MRI 교육 콘텐츠 학습효과 분석)

  • Jung-Hun Lee;Jae-Goo Shim
    • Journal of the Korean Society of Radiology
    • /
    • v.17 no.5
    • /
    • pp.775-782
    • /
    • 2023
  • In order to overcome practical limitations in installing, managing and operating MRI machines with expensive equipment, this study developed and utilized virtual reality (VR) experience education by combining virtual reality (VR) with magnetic resonance imaging devices. The Students who experienced virtual reality-based educational systems were surveyed to identify possible side effects during the experience and self-directed learning ability and academic self-efficacy surveys were conducted to analyze the impact of virtual reality-based practice on learning. In the analysis of the self-directed learning ability survey there was no difference in the average between the student group who experienced education and the student group who did not but there was a significant difference in the average for each group. Virtual Reality-based practical education is expected to provide an efficient practice system by providing new learning methods and opportunities for education that can be repeated anytime, anywhere regardless of time and space.

The segmentation system for the anatomical analysis and diagnosis simulation of multi-modality brain image (다중 모달리티 뇌 영상의 해부학적 분석 및 진단 시뮬레이션을 위한 영상분할 시스템)

  • 윤현주;이정민;김명희
    • Proceedings of the Korea Society for Simulation Conference
    • /
    • 2004.05a
    • /
    • pp.118-122
    • /
    • 2004
  • 본 논문에서는 인체의 머리 부분을 촬영한 의료 영상에서 뇌 영역만을 분할하는 방법에 대해 제시하고자 한다. 뇌의 해부학적 구조 및 기능적 이상 부위를 파악할 경우에 영상 내에 함께 보여지는 두개골과 뇌척수액 등을 제외한 대뇌피질 영역을 분할하면 보다 효과적인 정보 분석 및 진단이 가능하게 된다. 본 시스템에서는 3단계 알고리즘을 제시한다. 첫 번째 단계에서는 영상 내에 존재하는 잡음을 제거하기 위한 필터링이고, 두 번째 단계에서는 필터링된 결과에 대한 영상분할을 수행하는 것이다 이 때 정확한 결과 도출을 위하여 사용자의 인터렉션이 들어가게 된다. 세번째 단계에서는 형태학적 방법을 이용하여 분할 결과를 보완한다. 본 연구를 위한 실험에는 자기 공명 촬영 영상(MRI: Magnetic Resonance Imaging), 단일 광전자 방출 단층 촬영영상(SPECT: Single Photon Emission Computed Tomography), 양전자 방출 단층 촬영영상(PET: Positron Emission Tomography) 등을 사용하였다. 본 시스템에서는 다양한 모달리티의 뇌 영상에서 대뇌피질 부분을 정확하게 영상 분할함으로써 뇌의 구조적 이상을 판단하기 위한 해부학적 정보 분석을 가능케 하고 있다. 뿐만 아니라 뇌 질환에 대한 정확한 진단 시뮬레이션도 가능하게 하고자 한다.

  • PDF

Development of 1.0 Tesla Compact MRI System (1.0 Tesla 자기 공명 진단 장치의 개발)

  • Lee, H.K.;Oh, C.H.;Ahn, C.B.;Chang, Y.H.;Shin, D.W.;Lee, K.N.;Jang, K.H.
    • Proceedings of the KOSOMBE Conference
    • /
    • v.1996 no.11
    • /
    • pp.129-134
    • /
    • 1996
  • 1차 년도 G-7 개발 과제로 수행된 자기 공명 진단 장치 (Magnetic Resonance Imaging System)의 개발 내용을 간략히 소개하였다. 성공적인 IT Compact 자기 공명 진단 장치의 완성을 위해 일차적으로 (1)RF (고주파), Gradient(경사 자계), Spectrometer 등의 Hard-ware 관련 MRI 핵심부분, (2) RF, Gradient, Spectrometer, Magnet 등의 각 Sub-system을 연결, 조합, 조정하여 하나의 체계적인 시스템으로 통합하고 운영하는 과정(System Integration), (3)사용자와 시스템을 연결하는 User Interface, Data Base Management, Real time 운영 SW 등과 (4)임상에 적용하여 구체적인 성능과 효용성을 확인하는 기술 등에 대하여 집중 연구하였다. 개발 방법은 (1)지난 16년간 국내에 축적 된 연구 개발 인력들을 최대한 활용하고 (2)연구 개발을 국제화 시켜 필요한 경우 부분별로 개발 인력을 해외에서 보완하고 (3)소수 정예 전문 인력 주의와 요소 기술 또는 중요 부품을 경쟁성 검토 후 필요 시 Out-sourcing 활용으로 최저의 비용으로 개발 기간을 최소화 하는 데 두었다. 개발된 1.0Tesla자기 공명 영상 장치는 미국 물리 학회에서 규격화한 Phantom및 임상 적용을 통하여 서울대 의대 연구 팀과 지속적으로 성능을 평가해 왔다. 개발된 시스템의 해상도는 $256{\times}256$ head 영상에서 1mm 이 하의 해상도를 가짐을 resolution phantom 을 통하여 확인할 수 있었고, $512{\times}512$ 영상에서 는 약 0.5 mm 의 물체를 분리 해냄으로써 외제 시스템들 보다 우수하게 평가 되었다. 차폐 경사코일의 Eddy current영향은2%이내로 촬영 시 영향은 거의 무시할 수 있었다. 또한, 개발된 영상 기법들, 즉 Multislice/Multi Echo, Oblique angle imaging, 64 Echo train을 갖는 고속 촬영 기술들이 자기 공명 장치에 장착되어 임상 적용에 문제가 없도록 하였다. 또한 20mT/m/Amp의 강력한 능동 차폐 경사 자계 코일(Active Shield Gradient Coil)을 기본 사양으로 하고, 수신단을 최대 6개로 확장토록 하여 2차년도의 초고속 촬영 기법(EPI) 및 Phased Array 코일 촬영이 가능토록 하였다. 1차 년도 개발 과제 수행 결과와 향후 개발 과제를 바탕으로 최종 목표인 국제 경쟁력이 있는 자기 공명 진단 장치 즉 기능과 영상의 질은 선진국 제품과 동일하거나 우수하되, 저가격을 구현한 상용화 제품이 완성되어, 첨단 의료기기로서 산업 구조 고도화에 기여하고 수입대체 뿐만 아니 라 수출을 통한 국익 창출과 국가의 기술을 통한 위상 제고에 기여되길 기대한다.

  • PDF

Brain Trouble Detection of MRI Image using Markov Random Field (마르코프 랜덤 필드를 이용한 자기 공명 영상의 뇌질환 검출)

  • 조상현;염동훈;김태형;김두영
    • Proceedings of the Korea Institute of Convergence Signal Processing
    • /
    • 2003.06a
    • /
    • pp.1-5
    • /
    • 2003
  • 의료영상의 분할은 의료영상을 컴퓨터 진단 및 가시화에 필요한 같은 성질을 가진 여러 조직으로 나누어주는 방법이다. 즉 입력되어진 영상을 처리하여 유사한 화소들의 집합인 영역들로 화소들을 구분하는 작업이며 영상분할의 결과는 영상인식의 정확성에 큰 영향을 미친다. MRI(Magnetic Resonance Imaging)으로부터 정상적인 세포조직 또는 뇌종양과 같은 비정상적인 세포조직의 가시화와 분석을 위해서는 대상 세포조직의 적절한 분류를 필요로 한다. 하지만 기존의 영역 검출 방법으로는 잡음이 섞여 있는 영상에서 여러 가지의 처리과정(주로 잡음 제거)이 필수적이고 그런 과정으로 인해 정확한 영역 검출이 힘들게 된다. 이에 잡음이 있더라도 이를 제거하기 위한 처리가 필요 없이 영역기반으로 필요한 파라미터의 추정을 통한 MRF(Markov Random Field)를 이용하여 보다 효율적이고 정확하게 MRI에서 질환 영역을 검출할 수 있다.

  • PDF

Quasi-breath-hold (QBH) Biofeedback in Gated 3D Thoracic MRI: Feasibility Study (게이트 흉부자기 공명 영상법과 함께 사용할 수 있는 의사호흡정지(QBH) 바이오 피드백)

  • Kim, Taeho;Pooley, Robert;Lee, Danny;Keall, Paul;Lee, Rena;Kim, Siyong
    • Progress in Medical Physics
    • /
    • v.25 no.2
    • /
    • pp.72-78
    • /
    • 2014
  • The aim of the study is to test a hypothesis that quasi-breath-hold (QBH) biofeedback improves the residual respiratory motion management in gated 3D thoracic MR imaging, reducing respiratory motion artifacts with insignificant acquisition time alteration. To test the hypothesis five healthy human subjects underwent two gated MR imaging studies based on a T2 weighted SPACE MR pulse sequence using a respiratory navigator of a 3T Siemens MRI: one under free breathing and the other under QBH biofeedback breathing. The QBH biofeedback system utilized the external marker position on the abdomen obtained with an RPM system (Real-time Position Management, Varian) to audio-visually guide a human subject for 2s breath-hold at 90% exhalation position in each respiratory cycle. The improvement in the upper liver breath-hold motion reproducibility within the gating window using the QBH biofeedback system has been assessed for a group of volunteers. We assessed the residual respiratory motion management within the gating window and respiratory motion artifacts in 3D thoracic MRI both with/without QBH biofeedback. In addition, the RMSE (root mean square error) of abdominal displacement has been investigated. The QBH biofeedback reduced the residual upper liver motion within the gating window during MR acquisitions (~6 minutes) compared to that for free breathing, resulting in the reduction of respiratory motion artifacts in lung and liver of gated 3D thoracic MR images. The abdominal motion reduction in the gated window was consistent with the residual motion reduction of the diaphragm with QBH biofeedback. Consequently, average RMSE (root mean square error) of abdominal displacement obtained from the RPM has been also reduced from 2.0 mm of free breathing to 0.7 mm of QBH biofeedback breathing over the entire cycle (67% reduction, p-value=0.02) and from 1.7 mm of free breathing to 0.7 mm of QBH biofeedback breathing in the gated window (58% reduction, p-value=0.14). The average baseline drift obtained using a linear fit was reduced from 5.5 mm/min with free breathing to 0.6 mm/min (89% reduction, p-value=0.017) with QBH biofeedback. The study demonstrated that the QBH biofeedback improved the upper liver breath-hold motion reproducibility during the gated 3D thoracic MR imaging. This system can provide clinically applicable motion management of the internal anatomy for gated medical imaging as well as gated radiotherapy.

Lossless Deformation of Brain Images for Concealing Identification (신원 은닉을 위한 두뇌 영상의 무손실 변경)

  • Lee, Hyo-Jong;Yu, Du Ruo
    • The KIPS Transactions:PartB
    • /
    • v.18B no.6
    • /
    • pp.385-388
    • /
    • 2011
  • Patients' privacy protection is a heated issue in medical business, as medical information in digital format transmit everywhere through networks without any limitation. A current protection method for brain images is to deface from the brain image for patient's privacy. However, the defacing process often removes important brain voxels so that the defaced brain image is damaged for medical analysis. An ad-hoc method is proposed to conceal patient's identification by adding cylindrical mask, while the brain keep all important brain voxels. The proposed lossless deformation of brain image is verified not to loose any important voxels. Futhermore, the masked brain image is proved not to be recognized by others.

Paraovarian Serous Borderline Tumor: A Case Report (난소위체에서 발생한 장액성 경계성 종양: 증례 보고)

  • Hwang, Eun Taeg;Kim, See Hyung;Kim, Mi Jeong;Kang, Yu Na
    • Journal of the Korean Society of Radiology
    • /
    • v.79 no.6
    • /
    • pp.337-339
    • /
    • 2018
  • Parovarian cyst is usually simple cyst, and accounts for 10%-20% of adnexal masses. Borderline or malignant parovarian tumor is rare, and it contains papillary projection at the smooth inner wall. We report the ultrasonography, CT and MRI findings of a parovarian serous borderline tumor in 19-year-old female presenting left lower quadrant abdominal discomfort for 2 days.

Intracerebral Hemorrhage Caused by Thrombosis of a Developmental Venous Anomaly with an Unusual Structure: A Case Report (특이한 구조의 뇌정맥발달기형 내 혈전증에 의해 생긴 뇌출혈: 증례 보고)

  • Sunhyang Lee;Dae Yoon Kim;Mi Kyung Kim;Hyun Jin Kim
    • Journal of the Korean Society of Radiology
    • /
    • v.83 no.1
    • /
    • pp.199-205
    • /
    • 2022
  • Developmental venous anomalies (DVAs) are common intracranial vascular malformations and they are generally do not cause clinical complications. In cases showing DVA and hemorrhage, the hemorrhage is usually associated with adjacent cavernous malformations. Very few cases of intracerebral hemorrhage (ICH) caused by thrombosis in DVA have been reported in the literature. In this case report, we present an interesting case of a large ICH caused by thrombosis within a DVA with an unusual structure that may have potentiated the thrombosis.

Unsupervised Non-rigid Registration Network for 3D Brain MR images (3차원 뇌 자기공명 영상의 비지도 학습 기반 비강체 정합 네트워크)

  • Oh, Donggeon;Kim, Bohyoung;Lee, Jeongjin;Shin, Yeong-Gil
    • The Journal of Korean Institute of Next Generation Computing
    • /
    • v.15 no.5
    • /
    • pp.64-74
    • /
    • 2019
  • Although a non-rigid registration has high demands in clinical practice, it has a high computational complexity and it is very difficult for ensuring the accuracy and robustness of registration. This study proposes a method of applying a non-rigid registration to 3D magnetic resonance images of brain in an unsupervised learning environment by using a deep-learning network. A feature vector between two images is produced through the network by receiving both images from two different patients as inputs and it transforms the target image to match the source image by creating a displacement vector field. The network is designed based on a U-Net shape so that feature vectors that consider all global and local differences between two images can be constructed when performing the registration. As a regularization term is added to a loss function, a transformation result similar to that of a real brain movement can be obtained after the application of trilinear interpolation. This method enables a non-rigid registration with a single-pass deformation by only receiving two arbitrary images as inputs through an unsupervised learning. Therefore, it can perform faster than other non-learning-based registration methods that require iterative optimization processes. Our experiment was performed with 3D magnetic resonance images of 50 human brains, and the measurement result of the dice similarity coefficient confirmed an approximately 16% similarity improvement by using our method after the registration. It also showed a similar performance compared with the non-learning-based method, with about 10,000 times speed increase. The proposed method can be used for non-rigid registration of various kinds of medical image data.

Assesment Of Image Quality in the Abdominal Magnetic Resonance Imaging: Comparison with 1.5 T and 3.0 T (복부 자기공명영상에서 영상의 질 평가: 1.5 T 와 3.0 T 비교)

  • Goo, Eun-Hoe
    • Journal of the Korean Society of Radiology
    • /
    • v.10 no.5
    • /
    • pp.367-373
    • /
    • 2016
  • This study conducted an analysis to compare the differences in the properties of the magnetic field and the generation of artifacts because of the difference in the magnetic field between 1.5 T equipment and 3.0 T equipment, centering around four types of pulse sequences, mainly applied to the abdominal Magnetic Resonance Imaging (MRI). With data on 500 persons transmitted to the PACS, this study analyzed the SNR value, quantitatively and carried out a qualitative evaluation, dividing MSA, CSA, and DA into three steps. As a result of the quantitative evaluation, the SNR value was significantly higher in the 1.5 T equipment; however, there was a factor deteriorating the image quality, too, as artifacts were generated in the images. The 1.5 T equipment generated fewer artifacts than the 3.0 T equipment did, so it could compensate the image quality for 3.0 T. In conclusion, based on these findings, this study could understand the differences in the properties of the magnetic field and the generation of artifacts occurring because of the difference in the magnetic field and could provide a measure for them. This study would be guidelines for MRI users who directly examine the patients in abdominal MRI using the two types of equipment in the clinical setting in the future.